#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include <limits.h>
#define OJ_TEST 0
#define LOCAL_TEST 0

#define M 901

static int max(int a, int b){ return a>b?a:b; }
static int min(int a, int b) { return a<b?a:b; }

static void solve(void){
	int t, cs, a, b, sum;
	scanf("%d", &cs);
	for(t=1; t<=cs; ++t){
		scanf("%d%d", &a, &b);
		for(sum=0; a<=b; ++a){
			if(a%2) sum += a;
		}
		printf("Case %d: %d\n", t, sum);
	}
}
#if OJ_TEST
	int main(int ac, char *av[]){
		solve();
		return 0;
	}
#elif  LOCAL_TEST
	void run(void){
		solve();
	}

#else

#endif
